9.2: Intimate Relationships
Intimate relationships have the capacity to make us feel happy, healthy, and fulfilled. We experience higher self-efficacy, self-esteem, and positivity when we believe that our friends and partners are responding to us supportively, and with a concern for our needs and our own welfare. Our relationships with others help us buffer the negative effects of stress, avoid unhealthy behaviors, and cope with serious physical illness. And our close relationships allow us to express our fundamental desires to reach out and respond to other people.
Often, people point to a monogamous (having a sexual relationship with only one partner at a time), heterosexual, married couple to exemplify a loving and committed relationship. In most cultures around the world, heterosexuality, monogamy and marriage are perceived to be the standard type of relationship that all others are held in contrast to. However, there is far greater diversity in the types of loving and committed relationships. In this chapter, we will discuss a number of different relationships with differing views on monogamy, in terms of sexual orientation, and different views on whether to get married or to cohabit.
A recent film on the concept of monogamy explores the ways in which culture drives the types of relationships we consider. This film also delves into the ways in which we blame ourselves if we don’t thrive in a monogamous relationship. Monogamish | Official Trailer - Directed by Tao Ruspoli (Abramorama Films)
Same Sex Relationships
Social acceptance of same-sex relationships varies substantially throughout cultures and societies. Over the last few decades, same-sex relationships have changed more than heterosexual relationships. Some cultures became more tolerant and legally recognize same-sex unions. In the US marriage equality (same-sex marriage) was recognized and legalized nationwide in 2015. Research shows that same-sex and different-sex relationships operate in similar ways (Kurdek, 2004), and these couples tend to be as committed to each other and contented as different-sex couples, and the quality of their relationship is similar too.
Some Relationship Styles
Monogamous relationships are viewed positively in the modern Western world as relationships that promote strong commitment and health. Non-monogamy is often stigmatized and viewed as illegitimate. Half the states in the United States have laws against sex outside of marriage, although these laws are rarely enforced ( Sex and the Law | Nolo ). One study found that 75% of Americans believe that extramarital sex was unacceptable and should not be tolerated. However, the research on the incidence of extramarital affairs varies greatly. Many people think that sexual desire drives an extramarital affair; however, research has found that over 90% of extramarital affairs occur because the current relationship does not meet person’s emotional needs. Men are approximately three times more likely than women to say that a partner’s sexual intercourse with another person was more upsetting than a partner’s emotional attachment to that person (Shackelford, et al.). Men also find it more difficult than women to forgive sexual vs. emotional infidelity, and are more likely to say they would break up in response to sexual vs. emotional infidelity (Shackelford, et al.).
Some couples in committed relationships open up their relationship, and encourage their partners to have an extra-relationship affairs or to bring other partners into their bed, believing that sexual variety and experience may enhance their own sexual life. In an online survey (Rubin et al., 2014), 5% of participants said that they have an explicit agreement with their partner that they accept sexual or romantic pursuit outside of their relationship, and are practicing some form of consensual non-monogamy . According to a national US survey, about 21% reported that they were in some kind of open relationship at some point in their life. Consensual non-monogamy is also called ethical non-monogamy when involved parties strongly advocate for being honest with each other. Some people believe that consensual non-monogamy is one way to fight the habituation of desire, because introducing new sexual partners helps to keep sex interesting.
Open relationships generally have a “home base,” but partners are free to have other relationships at the same time. Some open relationships adopt a policy of non-disclosure, and some require full disclosure of their outside sexual experiences. Co-marital sex refers to the consenting of married couples to sexually exchange partners who are often referred to as swinging or polyamory . Polyamory is the idea that it is possible to love multiple people simultaneously. It is different from polygamy because a polyamorous person may or not be married, but the emphasis is mostly on building intimate relationships and not on recreational sex. Most couples who engage in co-marital sex have strict rules to protect their “home base” relationship, and see sex as separate from their loving long-term relationship.
Polygamy is the practice of having more than one spouse at a time. There are two types of polygamy arrangements: polygyny , when one man has multiple wives and polyandry , when one woman has multiple husbands. Both polygyny and polyandry are believed to be adaptive practices. Polygyny is rarely practiced in the United States. There are some small Mormon fundamentalist groups that practice it; however, they are not officially recognized by the Mormon Church. Polygyny was believed to have been developed in order to increase fertility to increase a greater number of offspring carrying a man’s gene. However, it is likely that polygyny developed as a strategy for men to gain prestige and power by having several wives, and for women to gain the protection of a wealthy and powerful man. Polyandry is a practice of having more than one husband at a time and it is less common that polygyny. It usually happens for a reason of keeping inheritance together, and to be protected from a scenario when just one partner may potentially have a gene defect.
Cohabitation and Marriage
In recent years the institution of marriage, the legally or formally recognized union of two people as partners in a personal relationship , has declined worldwide, but cohabitation has increased dramatically. (Cohn, Passel, Wang, & Livingston, 2011). Cohabitation is when a couple are living together in a sexual relationship when the partners are not legally married. Cohabitation has become so common that sociologists regard it as a stage of courtship. Cohabitation is sometimes, but not always, a precursor to marriage. It allows couples to learn more about each other’s habits and practices without being legally tied together. Cohabitation allows couples to mature together and create a partnership, regardless of if they decide to marry. Research shows that different-sex couples who cohabit are less likely to subscribe to traditional gender roles, and tend to have more equality in their relationships. (Blackwell & Lichter, 2000). However, at this point society as a whole does not legally recognize the cohabitation union for the purpose of health care, taxes, inheritance, etc. If a legal relationship is desired by people in cohabiting relationships, they can become domestic partners. Domestic Partnership , a legal relationship between couples, allows them to obtain many of the same benefits as a marriage, formalizing cohabitation. In the US, thirteen states recognize common-law marriage , which means that if a couple lives together for a certain number of years, they are automatically considered as married in the eyes of the law.
The meaning and purpose of marriage, and the manner in which spouses are selected, varies across cultures. For instance, in some cultures, like India, Pakistan, Bangladesh, China, and South Korea, the practice of arranged marriage, a marriage planned and agreed upon by the families of the couple to be married, is common, although the details differ depending on the cultural practices so not all arranged marriages look alike. These cultures tend to be collectivistic, where the needs of the family and community are placed above the needs of the individual. In contrast, Western cultures are considered to be more individualistic, and marriage is viewed as a matter of individual choice. Although many cultures have a tradition of arranged marriage, Western researchers interested in marital dynamics generally have focused on love-based marriages. A 2012 study entitled Relationship Outcomes in Indian-American Love-Based and Arranged Marriages by Regan et. al. compared relationship outcomes in love-based and arranged marriages contracted in the U.S. A community sample of 58 Indian participants living in the U.S. (28 arranged marriages, 30 love-based marriages) completed measures of marital satisfaction, commitment, companionate love, and passionate love. Men reported greater amounts of commitment, passionate love, and companionate love than women. Unexpectedly, no differences were found between participants in arranged and love-based marriages; high ratings of love, satisfaction, and commitment were observed in both marriage types. The overall affective experiences of partners in arranged and love marriages appear to be similar, at least among Indian adults living in contemporary U.S. society (Regan, Lakhanpal, Anguiano, 2012). According a 2012 study Reexamining the case for marriage: Union Formation and Changes in Wellbeing by Relationship by Musick, K. and Bampass, L. an advantage of a long-term relationship is better physical and psychological health than those who remain single, and these benefits extend to married and cohabitating partners as well (Musick & Bumpass, 2012). However, the study noted that being partnered provides more health benefits to men in heterosexual partnerships than women. The authors conclude that it is likely that those women studied tended to have more sources of social and emotional support outside of their primary relationships.
What is a relationship? As we learn, grow and inhabit (or discard) multiple intersectional identities, we have a variety of them throughout our lives. Relationships are important to most people as they help shape and determine both how we see and navigate through the world. How does bias and cultural norms dictate, implicitly and explicitly, the boundaries of these connections and roles. As individuals we can recognize that the types of relationships we might have are as fluid as other identities we are assigned or adopt through life; for example, spouse, partner, sibling, child, teenager, adult, parental guardian, friend, colleague, mentor, boss, teacher as well as gender and sexual identities. However, the most rigid normative relationship identity that is enforced through societal status is one of monogamy.
Monogamy in both heteronormative and queer relationships are often defined as a one-to-one partnership that is typically intimate and exclusionary of any other partner. This is the relationship style that is reinforced and held up as the only available option throughout most of western culture, society and media. To its credit, even considering the massive divorce rate, monogamy works great for a lot of people. Maybe it even works for you or someone you know but what about the folkx that it doesn’t work for? Equally fulfilling relationship styles and formations do exist but they are not the default. Polyamory is one such relationship identity that provides for romantic fulfillment similar to monogamy.
As monogamy is the default in most relationships, we have absorbed and internalized most of the unwritten and codified rules and boundaries that define a monogamous relationship. However, misconceptions abound when defining polyamory due to the bias and stereotypes imposed on it as the non-dominant style. Polyamory with its fluid construction is often wrongly portrayed in modern media as a replacement or in competition to monogamy when in fact it operates in parallel with it. Imagine both types as railroad tracks headed in the same direction rather than greater than/less than signs angrily pointed at each other.
Let’s talk about what a polyamorous relationship is and isn’t. Two major misconceptions are that it is strictly physical and it is just an excuse to cheat. Poly is often conflated with open relationships and/or swinging. These are not polyamorous relationships. Polyamorous relationships are defined by transparent communication and boundary setting as well as the consent of all parties. Considering that relationships types under the polygamous umbrella are mutually self-defined and fluid, it is challenging to strictly define all the variations that exist but in general they fall into a few loosely defined categories.
The most common types of polyamory are partner-plus; egalitarian network partnerships sometimes referred to as relationship anarchy (RA) and solo or centered polyamory. All of these might also have attributes and agreements that can include terms like ethical non-monogamy, poly-secure and poly-fidelity. Partner-plus is typically additive and hierarchical; for example, this is when two partners (who are typically married or in a long-term relationship) add a third or fourth individual partner but the activities that those additive partners engage in are well-defined and secondary. Imagine that Alex and Jaiden are the primary partners in a relationship, a third partner, Dylan who is dating Alex share some relationship characteristics and intimacy like going on dates and engaging in shared interests. However, Dylan isn’t included in making large primary relationship decisions for Alex and Jaiden like where to live, career advancement and child-rearing. Egalitarian network partnerships or relationship anarchy polyamory, in contrast and as the name suggests operate in a non-hierarchical fashion. Imagine Billy, Dakota and Kai are in this type of poly relationship: No one partner is the primary partner, all partners have an equitable share in making long-term relationship decisions. This is perhaps the most common type of polyamorous relationship making up the majority of the twenty or so percent of folkx in the United States and Canada who are poly and is commonly called a thruple. Thruples are also often characterized as having poly-fidelity or being a closed intimate relationship between the three partners. Solo polyamory is less common but is growing in popularity especially among individuals who identify as asexual, aero or ace. Individuals who engage in these types of relationships often never marry or live with their partners and can be described colloquially as “living together, apart”.
A common reaction to these types of relationships is one of, “I can never do that, I would get jealous.” Jealousy is, of course, not unique to either monogamous or polyamorous relationships. Surprisingly, most long-term poly relationships have a lower reporting rate of jealousy as the reason for breaking up and ending. The research suggests that this is due to the increased focus on transparent communication and consent, emotional literacy and the purposeful development of compersion within the relationship. Compersion -the joy of seeing others experience joy- isn’t often an emotion that is explicitly discussed within monogamous relationships as it is intertwined with its opposites, namely jealousy and shame. Individuals who practice polyamory cultivate and recognize compersion for their partner by acknowledging that jealousy is inevitable in all relationships: Instead of burying those feelings of jealousy in shame and hurt, they celebrate the joys of their partners even if they aren’t the direct source of that joy.
Obviously, successful long-term polyamorous relationships exist and these relationships often share the same goals as monogamous relationships using the definitions above. Why then are they impacted by bias and discrimination when viewed through a western lens. One answer might be found by examining both the historical and economic pressures of long-term relationships as well as the sociological construction of the individualistic family unit. Historically, many marriages were seen as transactional often for financial or political security. Highlighting and following this trend from the 18 th and 19 th century well into the explosive growth of corporate capitalism in 1940’s and 50’s America, it aligns with the most successful marketing campaign of the last century. The diamond is forever campaign by DeBeers is synonymous with equating monetary worth, winning and competitive success with values like monogamy, love and the normative family unit. It is also synonymous with conflict diamonds, monopolization of both the supply and demand side of a natural resource as well as the creation and perpetuation of what is today’s exploitative wedding industry. These norms often work in concert with imagery found throughout media like the Disneyfication of relationship roles which infantize both parties as well as movies and music that capitalize on the idea that one (and only one) special partner should be able to fulfill all the needs in a relationship and that partner must be “won” and “possessed” forever. This seems to mirror and reinforce the idea that the only relationship of value and worth is one that holds the shape of monogamy. This stands in opposition with a more communal pooling of resources for duties like family planning or child rearing common in more non-western facing cultures.
Why is monogamy the default while long-term polyamorous relationships are frequently looked upon with bias and derision? Perhaps, it is only a coincidence that the type of monogamy that is continually reinforced via media, cultural norms and government practices often benefit those that sell the idea of the one and only relationship model often to the financial detriment of the individual couple.


5.4: The Destruction of the Tea and the Coercive Acts
The Tea Act of 1773 triggered a reaction with far more significant consequences than either the 1765 Stamp Act or the 1767 Townshend Acts. Colonists who had joined in protest against those earlier acts renewed their efforts in 1773. They understood that Parliament had again asserted its right to impose taxes without representation, and they feared the Tea Act was designed to seduce them into conceding this important principle by lowering the price of tea to the point that colonists might abandon their scruples. They also deeply resented the East India Company’s monopoly on the sale of tea in the American colonies; this resentment sprang from the knowledge that some members of Parliament had invested heavily in the company.
SMOLDERING RESENTMENT
Even after the partial repeal of the Townshend duties, however, suspicion of Parliament’s intentions remained high. This was especially true in port cities like Boston and New York, where British customs agents were a daily irritant and reminder of British power. In public houses and squares, people met and discussed politics. Philosopher John Locke’s Two Treatises of Government , published almost a century earlier, influenced political thought about the role of government to protect life, liberty, and property. The Sons of Liberty issued propaganda ensuring that colonists remained aware when Parliament overreached itself.
Violence continued to break out on occasion, as in 1772, when Rhode Island colonists boarded and burned the British revenue ship Gaspée in Narragansett Bay (Figure 5.4.1). Colonists had attacked or burned British customs ships in the past, but after the Gaspée Affair, the British government convened a Royal Commission of Inquiry. This Commission had the authority to remove the colonists, who were charged with treason, to Great Britain for trial. Some colonial protestors saw this new ability as another example of the overreach of British power.
Samuel Adams, along with Joseph Warren and James Otis, re-formed the BostonCommittee of Correspondence, which functioned as a form of shadow government, to address the fear of British overreach. Soon towns all over Massachusetts had formed their own committees, and many other colonies followed suit. These committees, which had between seven and eight thousand members in all, identified enemies of the movement and communicated the news of the day. Sometimes they provided a version of events that differed from royal interpretations, and slowly, the committees began to supplant royal governments as sources of information. They later formed the backbone of communication among the colonies in the rebellion against the Tea Act, and eventually in the revolt against the British crown.
THE TEA ACT OF 1773
Parliament did not enact the Tea Act of 1773 in order to punish the colonists, assert parliamentary power, or even raise revenues. Rather, the act was a straightforward order of economic protectionism for a British tea firm, the East India Company, that was on the verge of bankruptcy. In the colonies, tea was the one remaining consumer good subject to the hated Townshend duties. Protest leaders and their followers still avoided British tea, drinking smuggled Dutch tea as a sign of patriotism.
The Tea Act of 1773 gave the British East India Company the ability to export its tea directly to the colonies without paying import or export duties and without using middlemen in either Great Britain or the colonies. Even with the Townshend tax, the act would allow the East India Company to sell its tea at lower prices than the smuggled Dutch tea, thus undercutting the smuggling trade.
This act was unwelcome to those in British North America who had grown displeased with the pattern of imperial measures. By granting a monopoly to the East India Company, the act not only cut out colonial merchants who would otherwise sell the tea themselves; it also reduced their profits from smuggled foreign tea. These merchants were among the most powerful and influential people in the colonies, so their dissatisfaction carried some weight. Moreover, because the tea tax that the Townshend Acts imposed remained in place, tea had intense power to symbolize the idea of “no taxation without representation.”
COLONIAL PROTEST: THE DESTRUCTION OF THE TEA
The 1773 act reignited the worst fears among the colonists. To the Sons and Daughters of Liberty and those who followed them, the act appeared to be proof positive that a handful of corrupt members of Parliament were violating the British Constitution. Veterans of the protest movement had grown accustomed to interpreting British actions in the worst possible light, so the 1773 act appeared to be part of a large conspiracy against liberty.
As they had done to protest earlier acts and taxes, colonists responded to the Tea Act with a boycott. The Committees of Correspondence helped to coordinate resistance in all of the colonial port cities, so up and down the East Coast, British tea-carrying ships were unable to come to shore and unload their wares. In Charlestown, Boston, Philadelphia, and New York, the equivalent of millions of dollars’ worth of tea was held hostage, either locked in storage warehouses or rotting in the holds of ships as they were forced to sail back to Great Britain.
In Boston, Thomas Hutchinson, now the royal governor of Massachusetts, vowed that radicals like Samuel Adams would not keep the ships from unloading their cargo. He urged the merchants who would have accepted the tea from the ships to stand their ground and receive the tea once it had been unloaded. When the Dartmouth sailed into Boston Harbor in November 1773, it had twenty days to unload its cargo of tea and pay the duty before it had to return to Great Britain. Two more ships, the Eleanor and the Beaver , followed soon after. Samuel Adams and the Sons of Liberty tried to keep the captains of the ships from paying the duties and posted groups around the ships to make sure the tea would not be unloaded.
On December 16, just as the Dartmouth ’s deadline approached, townspeople gathered at the Old South Meeting House determined to take action. From this gathering, a group of Sons of Liberty and their followers approached the three ships. Some were disguised as Mohawks. Protected by a crowd of spectators, they systematically dumped all the tea into the harbor, destroying goods worth almost $1 million in today’s dollars, a very significant loss. This act soon inspired further acts of resistance up and down the East Coast. However, not all colonists, and not even all Patriots, supported the dumping of the tea. The wholesale destruction of property shocked people on both sides of the Atlantic.
To learn more about the Boston Tea Party, explore the extensive resources in the Boston Tea Party Ships and Museum collection of articles, photos, and video. At the museum itself, you can board replicas of the Eleanor and the Beaver and experience a recreation of the dumping of the tea.
PARLIAMENT RESPONDS: THE COERCIVE ACTS
In London, response to the destruction of the tea was swift and strong. The violent destruction of property infuriated King George III and the prime minister, Lord North (Figure 5.4.2), who insisted the loss be repaid. Though some American merchants put forward a proposal for restitution, the Massachusetts Assembly refused to make payments. Massachusetts’s resistance to British authority united different factions in Great Britain against the colonies. North had lost patience with the unruly British subjects in Boston. He declared: “The Americans have tarred and feathered your subjects, plundered your merchants, burnt your ships, denied all obedience to your laws and authority; yet so clement and so long forbearing has our conduct been that it is incumbent on us now to take a different course. Whatever may be the consequences, we must risk something; if we do not, all is over.” Both Parliament and the king agreed that Massachusetts should be forced to both pay for the tea and yield to British authority.
In early 1774, leaders in Parliament responded with a set of four measures designed to punish Massachusetts, commonly known at the Coercive Acts. The Boston Port Bill shut down Boston Harbor until the East India Company was repaid. The Massachusetts Government Act placed the colonial government under the direct control of crown officials and made traditional town meetings subject to the governor’s approval. The Administration of Justice Act allowed the royal governor to unilaterally move any trial of a crown officer out of Massachusetts, a change designed to prevent hostile Massachusetts juries from deciding these cases. This act was especially infuriating to John Adams and others who emphasized the time-honored rule of law. They saw this part of the Coercive Acts as striking at the heart of fair and equitable justice. Finally, the Quartering Act encompassed all the colonies and allowed British troops to be housed in occupied buildings.
At the same time, Parliament also passed the Quebec Act, which expanded the boundaries of Quebec westward and extended religious tolerance to Roman Catholics in the province. For many Protestant colonists, especially Congregationalists in New England, this forced tolerance of Catholicism was the most objectionable provision of the act. Additionally, expanding the boundaries of Quebec raised troubling questions for many colonists who eyed the West, hoping to expand the boundaries of their provinces. The Quebec Act appeared gratuitous, a slap in the face to colonists already angered by the Coercive Acts.
American Patriots renamed the Coercive and Quebec measures the Intolerable Acts. Some in London also thought the acts went too far; see the cartoon “The Able Doctor, or America Swallowing the Bitter Draught” (Figure 5.4.3) for one British view of what Parliament was doing to the colonies. Meanwhile, punishments designed to hurt only one colony (Massachusetts, in this case) had the effect of mobilizing all the colonies to its side. The Committees of Correspondence had already been active in coordinating an approach to the Tea Act. Now the talk would turn to these new, intolerable assaults on the colonists’ rights as British subjects.
Section Summary
The colonial rejection of the Tea Act, especially the destruction of the tea in Boston Harbor, recast the decade-long argument between British colonists and the home government as an intolerable conspiracy against liberty and an excessive overreach of parliamentary power. The Coercive Acts were punitive in nature, awakening the worst fears of otherwise loyal members of the British Empire in America.
Review Questions
Which of the following is true of the Gaspée affair?
- Colonists believed that the British response represented an overreach of power.
- It was the first time colonists attacked a revenue ship.
- It was the occasion of the first official death in the war for independence.
- The ship’s owner, John Hancock, was a respectable Boston merchant.
A
What was the purpose of the Tea Act of 1773?
- to punish the colonists for their boycotting of British tea
- to raise revenue to offset the British national debt
- to help revive the struggling East India Company
- to pay the salaries of royal appointees
C
What was the significance of the Committees of Correspondence?
The Committees of Correspondence provided a crucial means of communication among the colonies. They also set the foundation for a colonial government by breaking away from royal governmental structures. Finally, they promoted a sense of colonial unity.
Glossary
- Coercive Acts
- four acts (Administration of Justice Act, Massachusetts Government Act, Port Bill, Quartering Act) that Lord North passed to punish Massachusetts for destroying the tea and refusing to pay for the damage
- Committees of Correspondence
- colonial extralegal shadow governments that convened to coordinate plans of resistance against the British
- Intolerable Acts
- the name American Patriots gave to the Coercive Acts and the Quebec Act


18.2: An Overview of Blood
By the end of this section, you will be able to:
- Identify the primary functions of blood in transportation, defense, and maintenance of homeostasis
- Name the fluid component of blood and the three major types of formed elements, and identify their relative proportions in a blood sample
- Discuss the unique physical characteristics of blood
- Identify the composition of blood plasma, including its most important solutes and plasma proteins
Recall that blood is a connective tissue. Like all connective tissues, it is made up of cellular elements and an extracellular matrix. The cellular elements—referred to as the formed elements —include red blood cells (RBCs) , white blood cells (WBCs) , and cell fragments called platelets . The extracellular matrix, called plasma , makes blood unique among connective tissues because it is fluid. This fluid, which is mostly water, perpetually suspends the formed elements and enables them to circulate throughout the body within the cardiovascular system.
Functions of Blood
The primary function of blood is to deliver oxygen and nutrients to and remove wastes from body cells, but that is only the beginning of the story. The specific functions of blood also include defense, distribution of heat, and maintenance of homeostasis.
Transportation
Nutrients from the foods you eat are absorbed in the digestive tract. Most of these travel in the bloodstream directly to the liver, where they are processed and released back into the bloodstream for delivery to body cells. Oxygen from the air you breathe diffuses into the blood, which moves from the lungs to the heart, which then pumps it out to the rest of the body. Moreover, endocrine glands scattered throughout the body release their products, called hormones, into the bloodstream, which carries them to distant target cells. Blood also picks up cellular wastes and byproducts, and transports them to various organs for removal. For instance, blood moves carbon dioxide to the lungs for exhalation from the body, and various waste products are transported to the kidneys and liver for excretion from the body in the form of urine or bile.
Defense
Many types of WBCs protect the body from external threats, such as disease-causing bacteria that have entered the bloodstream in a wound. Other WBCs seek out and destroy internal threats, such as cells with mutated DNA that could multiply to become cancerous, or body cells infected with viruses.
When damage to the vessels results in bleeding, blood platelets and certain proteins dissolved in the plasma, the fluid portion of the blood, interact to block the ruptured areas of the blood vessels involved. This protects the body from further blood loss.
Maintenance of Homeostasis
Recall that body temperature is regulated via a classic negative-feedback loop. If you were exercising on a warm day, your rising core body temperature would trigger several homeostatic mechanisms, including increased transport of blood from your core to your body periphery, which is typically cooler. As blood passes through the vessels of the skin, heat would be dissipated to the environment, and the blood returning to your body core would be cooler. In contrast, on a cold day, blood is diverted away from the skin to maintain a warmer body core. In extreme cases, this may result in frostbite.
Blood also helps to maintain the chemical balance of the body. Proteins and other compounds in blood act as buffers, which thereby help to regulate the pH of body tissues. Blood also helps to regulate the water content of body cells.
Composition of Blood
You have probably had blood drawn from a superficial vein in your arm, which was then sent to a lab for analysis. Some of the most common blood tests—for instance, those measuring lipid or glucose levels in plasma—determine which substances are present within blood and in what quantities. Other blood tests check for the composition of the blood itself, including the quantities and types of formed elements.
One such test, called a hematocrit , measures the percentage of RBCs, clinically known as erythrocytes, in a blood sample. It is performed by spinning the blood sample in a specialized centrifuge, a process that causes the heavier elements suspended within the blood sample to separate from the lightweight, liquid plasma (Figure \(\PageIndex{1}\) ). Because the heaviest elements in blood are the erythrocytes, these settle at the very bottom of the hematocrit tube. Located above the erythrocytes is a pale, thin layer composed of the remaining formed elements of blood. These are the WBCs, clinically known as leukocytes, and the platelets, cell fragments also called thrombocytes. This layer is referred to as the buffy coat because of its color; it normally constitutes less than 1 percent of a blood sample. Above the buffy coat is the blood plasma, normally a pale, straw-colored fluid, which constitutes the remainder of the sample.
The volume of erythrocytes after centrifugation is also commonly referred to as packed cell volume (PCV) . In normal blood, about 45 percent of a sample is erythrocytes. The hematocrit of any one sample can vary significantly, however, about 36–50 percent, according to gender and other factors. Normal hematocrit values for females range from 37 to 47, with a mean value of 41; for males, hematocrit ranges from 42 to 52, with a mean of 47. The percentage of other formed elements, the WBCs and platelets, is extremely small so it is not normally considered with the hematocrit. So the mean plasma percentage is the percent of blood that is not erythrocytes: for females, it is approximately 59 (or 100 minus 41), and for males, it is approximately 53 (or 100 minus 47).
Characteristics of Blood
When you think about blood, the first characteristic that probably comes to mind is its color. Blood that has just taken up oxygen in the lungs is bright red, and blood that has released oxygen in the tissues is a more dusky red. This is because hemoglobin is a pigment that changes color, depending upon the degree of oxygen saturation.
Blood is viscous and somewhat sticky to the touch. It has a viscosity approximately five times greater than water. Viscosity is a measure of a fluid’s thickness or resistance to flow, and is influenced by the presence of the plasma proteins and formed elements within the blood. The viscosity of blood has a dramatic impact on blood pressure and flow. Consider the difference in flow between water and honey. The more viscous honey would demonstrate a greater resistance to flow than the less viscous water. The same principle applies to blood.
The normal temperature of blood is slightly higher than normal body temperature—about 38 °C (or 100.4 °F), compared to 37 °C (or 98.6 °F) for an internal body temperature reading, although daily variations of 0.5 °C are normal.  This accounts for its slightly higher temperature.
The pH of blood averages about 7.4; however, it can range from 7.35 to 7.45 in a healthy person. Blood is therefore somewhat more basic (alkaline) on a chemical scale than pure water, which has a pH of 7.0. Blood contains numerous buffers that actually help to regulate pH.
Blood constitutes approximately 8 percent of adult body weight. Adult males typically average about 5 to 6 liters of blood. Females average 4–5 liters.
Blood Plasma
Like other fluids in the body, plasma is composed primarily of water: In fact, it is about 92 percent water. Dissolved or suspended within this water is a mixture of substances, most of which are proteins. There are literally hundreds of substances dissolved or suspended in the plasma, although many of them are found only in very small quantities.
Interactive Link
Visit this site for a list of normal levels established for many of the substances found in a sample of blood. Serum, one of the specimen types included, refers to a sample of plasma after clotting factors have been removed. What types of measurements are given for levels of glucose in the blood?
Plasma Proteins
About 7 percent of the volume of plasma—nearly all that is not water—is made of proteins. These include several plasma proteins (proteins that are unique to the plasma), plus a much smaller number of regulatory proteins, including enzymes and some hormones. The major components of plasma are summarized in Figure 18.3.
The three major groups of plasma proteins are as follows:
- Albumin is the most abundant of the plasma proteins. Manufactured by the liver, albumin molecules serve as binding proteins—transport vehicles for fatty acids and steroid hormones. Recall that lipids are hydrophobic; however, their binding to albumin enables their transport in the watery plasma. Albumin is also the most significant contributor to the osmotic pressure of blood; that is, its presence holds water inside the blood vessels and draws water from the tissues, across blood vessel walls, and into the bloodstream. This in turn helps to maintain both blood volume and blood pressure. Albumin normally accounts for approximately 54 percent of the total plasma protein content, in clinical levels of 3.5–5.0 g/dL blood.
- The second most common plasma proteins are the globulins . A heterogeneous group, there are three main subgroups known as alpha, beta, and gamma globulins. The alpha and beta globulins transport iron, lipids, and the fat-soluble vitamins A, D, E, and K to the cells; like albumin, they also contribute to osmotic pressure. The gamma globulins are proteins involved in immunity and are better known as an antibodies or immunoglobulins . Although other plasma proteins are produced by the liver, immunoglobulins are produced by specialized leukocytes known as plasma cells. (Seek additional content for more information about immunoglobulins.) Globulins make up approximately 38 percent of the total plasma protein volume, in clinical levels of 1.0–1.5 g/dL blood.
- Fibrinogen is the third of the three major groups of plasma proteins. Like albumin and the alpha and beta globulins, fibrinogen is produced by the liver. It is essential for blood clotting, a process described later in this chapter. Fibrinogen accounts for about 7 percent of the total plasma protein volume, in clinical levels of 0.2–0.45 g/dL blood.
Other Plasma Solutes
In addition to proteins, plasma contains a wide variety of other substances. These include various electrolytes, such as sodium, potassium, and calcium ions; dissolved gases, such as oxygen, carbon dioxide, and nitrogen; various organic nutrients, such as vitamins, lipids, glucose, and amino acids; and metabolic wastes. All of these nonprotein solutes combined contribute approximately 1 percent to the total volume of plasma.
|
Component and % of blood |
Subcomponent and % of component |
Type and % (where appropriate) |
Site of production |
Major function(s) |
|
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Water 92 percent |
Fluid |
Absorbed by intestinal tract or produced by metabolism |
Transport medium |
|
|
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Albumin 54-60 percent |
Liver |
Maintain osmotic concentration, transport lipid molecules |
|
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Plasma proteins 7 percent |
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Alpha globulins— liver |
Transport, maintain osmotic concentration |
|
Plasma 46-63 percent |
Globulins 35-38 percent |
Beta globulins— liver |
Transport, maintain osmotic concentration |
|
|
|
|
Gamma globulins (immunoglobulins) —plasma cells |
Immune responses |
|
|
|
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Fibrinogen 4-7 percent |
Liver |
Blood clotting in hemostasis |
|
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Regulatory proteins <1 percent |
Hormones and enzymes |
Various sources |
Regulate various body functions |
|
|
Other solutes 1 percent |
Nutrients, gases, and wastes |
Absorbed by intestinal tract, exchanged in respiratory system, or produced by cells |
Numerous and varied |
|
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Erythrocytes 99 percent |
Erythrocytes |
Red bone marrow |
Transport gases, primarily oxygen and some carbon dioxide |
|
Formed elements 37-54 |
Leukocytes <1 percent Platelets <1 percent |
Granular leukocytes: neutrophils eosinophils basophils |
Red bone marrow |
Nonspecific immunity |
|
percent |
Agranular leukocytes: lymphocytes monocytes |
Lymphocytes: bone marrow and lymphatic tissue |
Lymphocytes: specific immunity |
|
|
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Monocytes: red bone marrow |
Monocytes: nonspecific immunity |
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Platelets <1 percent |
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Megakaryocytes: red bone marrow |
Hemostasis |
Career Connection
Phlebotomy and Medical Lab Technology
Phlebotomists are professionals trained to draw blood (phleb- = “a blood vessel”; -tomy = “to cut”). When more than a few drops of blood are required, phlebotomists perform a venipuncture, typically of a surface vein in the arm.  An arterial stick is collected from an artery and used to analyze blood gases. After collection, the blood may be analyzed by medical laboratories or perhaps used for transfusions, donations, or research. While many allied health professionals practice phlebotomy, the American Society of Phlebotomy Technicians issues certificates to individuals passing a national examination, and some large labs and hospitals hire individuals expressly for their skill in phlebotomy.
Medical or clinical laboratories employ a variety of individuals in technical positions:
- Medical technologists (MT), also known as clinical laboratory technologists (CLT), typically hold a bachelor’s degree and certification from an accredited training program. They perform a wide variety of tests on various body fluids, including blood. The information they provide is essential to the primary care providers in determining a diagnosis and in monitoring the course of a disease and response to treatment.
- Medical laboratory technicians (MLT) typically have an associate’s degree but may perform duties similar to those of an MT.
- Medical laboratory assistants (MLA) spend the majority of their time processing samples and carrying out routine assignments within the lab. Clinical training is required, but a degree may not be essential to obtaining a position.


6.6: Social Money
It’s out there
Let’s assume for a minute you’ve decided to become a social entrepreneur. Getting money for your socially beneficial startup isn’t so different from the standard process, save one thing: there are many organizations that exist primarily to give social entrepreneurs money. They’re part of a vast and fast-growing network of people dedicated to change through Socially Responsible Investing (SRI).
Investing for the cause
At a basic level, SRI is the marriage of social responsibility and environmental sustainability to investment. It includes all the financial decision-making processes that go into a prudent investment management approach, but also includes the selection and management of investments based on issues of sustainability and social responsibility.1 There are three general investment strategies at work in SRI:
Screening
Screening means investing in companies that do good and avoiding ones that do bad. Socially responsible investors ask their investment advisors to overlay a qualitative analysis of corporate policies, practices, attitudes and environmental impacts on top of the traditional quantitative analysis of profit potential. This means investing in enterprises with outstanding employee and environmental policies that make and sell safe, useful products and demonstrate respect for human rights worldwide. Companies on the outs typically include child labor law violators, tobacco, manufacturers of environmentally damaging products, and other who potentially inflict social harm.
Community investing
Community investing provides capital to people in low-income, at-risk communities who have difficulty getting money through conventional channels. Many social investors earmark a percentage of their investments to community development financial institutions (CDFIs) that work to alleviate poverty, create jobs, and provide affordable housing and small business development financing in disadvantaged communities.
Shareholder advocacy
Also called shareholder activism, this means engaging in dialogue with companies and submitting and voting on shareholder resolutions. Action is focused on positively influencing corporate behavior. Socially conscious investors often work to steer management on a course they believe will improve financial performance over time and enhance the well-being of all of the company’s stakeholders—customers, employees, vendors, communities, the environment and stockholders.
One serious growth industry
SRI is hot. In 2003, the Social Investment Forum, in its bi-annual Report on Socially Responsible Investing Trends in the US, cited $2.16 trillion involved in one or more of the three primary socially responsible investment strategies—nearly four times the $639 billion the Forum identified in 1995.
Assets under professional management involved in social screening, shareholder advocacy, and community investing have grown nearly 40% faster than all professionally managed investment assets in the US. Between 1995 and 2003, SRI experienced 240% growth versus 174% general market growth.
The growth of socially screened portfolios is even more dramatic: from $165 billion in 1995 to over $2 trillion in 2003. In 2003, socially responsible portfolios accounted for 11.3% of the investment assets under professional management in the US.
Fellows programs, venture philanthropy
Many people want to invest in good causes, but SRI funds invest in established companies. How do you, as a fledgling social entrepreneur, get funded? Check out the following organizations:
Acumen Fund is a non-profit enterprise focused on improving the lives of the poor around the world. They operate like a venture capital firm—investing philanthropic resources in innovative social entrepreneurs with a goal of social change rather than financial return.
Investors’ Circle (IC) is a non-profit national network of angel and institutional investors, foundation officers and entrepreneurs who seek to achieve financial, social and environmental returns.
Ashoka is a global organization that searches the world for social entrepreneurs—extraordinary individuals with unprecedented ideas for change in their communities.
Echoing Green’s mission is to spark social change by identifying, investing in and supporting the world’s most exceptional emerging leaders and the organizations they launch. Through a two-year fellowship program, they help develop new solutions to society’s most difficult problems.
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More resources
High tech social entrepreneurship
Useful links
Non-profit boom
From www.fastcompany.com/social/intro.html It's a real career David Bornstein, author of How to Change the World: Social Entrepreneurs and the Power of New Ideas, speaks on the bright future of the social entrepreneurship industry: "One thing for individuals to think about is that this field has become a legitimate career path. For those who are still in school, or considering a career change, the field of social entrepreneurship is rapidly growing to encompass all sorts of jobs with all sorts of job descriptions. As an individual, you have plenty of opportunities to work in a way that is challenging, impactful, and deeply meaningful." From www.fastcompany.com/social/ideas.html |


21.3: Kirchhoff’s Rules
Learning Objectives
By the end of this section, you will be able to:
- Analyze a complex circuit using Kirchhoff’s rules, using the conventions for determining the correct signs of various terms.
Many complex circuits, such as the one in Figure \(\PageIndex{1}\), cannot be analyzed with the series-parallel techniques developed in Resistors in Series and Parallel and Electromotive Force: Terminal Voltage . There are, however, two circuit analysis rules that can be used to analyze any circuit, simple or complex. These rules are special cases of the laws of conservation of charge and conservation of energy. The rules are known as Kirchhoff’s rules , after their inventor Gustav Kirchhoff (1824–1887).
Definition: Kirchhoff's Rules
- Kirchhoff’s first rule—the junction rule: The sum of all currents entering a junction must equal the sum of all currents leaving the junction.
- Kirchhoff’s second rule—the loop rule: The algebraic sum of changes in potential around any closed circuit path (loop) must be zero.
Explanations of the two rules will now be given, followed by problem-solving hints for applying Kirchhoff’s rules, and a worked example that uses them.
Kirchhoff’s First Rule (The Junction Rule)
Kirchhoff’s first rule (the junction rule ) is an application of the conservation of charge to a junction; it is illustrated in Figure \(\PageIndex{2}\). Current is the flow of charge, and charge is conserved; thus, whatever charge flows into the junction must flow out. Kirchhoff’s first rule requires that \(I_1 = I_2 + I_3\) (Figure \(\PageIndex{2}\)). Equations like this can and will be used to analyze circuits and to solve circuit problems.
Kirchhoff’s Second Rule (The Loop Rule)
Kirchhoff’s second rule (the loop rule ) is an application of conservation of energy. The loop rule is stated in terms of potential, rather than potential energy, but the two are related since \(PE_{elec} = qV\). Recall that emf is the potential difference of a source when no current is flowing. In a closed loop, whatever energy is supplied by emf must be transferred into other forms by devices in the loop, since there are no other ways in which energy can be transferred into or out of the circuit. Figure \(\PageIndex{3}\) illustrates the changes in potential in a simple series circuit loop.
Kirchhoff’s second rule requires \(emf - Ir - IR_1 - IR_2 = 0\). Rearranged, this is \(emf = Ir + IR_1 + IR_2\), which means the emf equals the sum of the \(IR\) (voltage) drops in the loop.
Applying Kirchhoff’s Rules
By applying Kirchhoff’s rules, we generate equations that allow us to find the unknowns in circuits. The unknowns may be currents, emfs, or resistances. Each time a rule is applied, an equation is produced. If there are as many independent equations as unknowns, then the problem can be solved. There are two decisions you must make when applying Kirchhoff’s rules. These decisions determine the signs of various quantities in the equations you obtain from applying the rules.
- When applying Kirchhoff’s first rule, the junction rule, you must label the current in each branch and decide in what direction it is going. For example, in Figure , Figure , and Figure , currents are labeled \(I_1, \, I_2, \, I_3\) and \(I\), and arrows indicate their directions. There is no risk here, for if you choose the wrong direction, the current will be of the correct magnitude but negative.
- When applying Kirchhoff’s second rule, the loop rule, you must identify a closed loop and decide in which direction to go around it, clockwise or counterclockwise. For example, in Figure the loop was traversed in the same direction as the current (clockwise). Again, there is no risk; going around the circuit in the opposite direction reverses the sign of every term in the equation, which is like multiplying both sides of the equation by -1.
Figure \(\PageIndex{4}\) and the following points will help you get the plus or minus signs right when applying the loop rule. Note that the resistors and emfs are traversed by going from a to b. In many circuits, it will be necessary to construct more than one loop. In traversing each loop, one needs to be consistent for the sign of the change in potential (Example \(\PageIndex{1}\)).
- When a resistor is traversed in the same direction as the current, the change in potential is \(-IR\). (See Figure .)
- When a resistor is traversed in the direction opposite to the current, the change in potential is \(+IR\). (See Figure .)
- When an emf is traversed from - to + (the same direction it moves positive charge), the change in potential is +emf. (See Figure .)
- When an emf is traversed from + to - (opposite to the direction it moves positive charge), the change in potential is -emf. (See Figure .)
Example \(\PageIndex{1}\): Calculating Current: Using Kirchhoff’s Rules
Find the currents flowing in the circuit in Figure \(\PageIndex{5}\).
Strategy
This circuit is sufficiently complex that the currents cannot be found using Ohm’s law and the series-parallel techniques—it is necessary to use Kirchhoff’s rules. Currents have been labeled \(I_1, \, I_2,\) and \(I_3\)
in the figure and assumptions have been made about their directions. Locations on the diagram have been labeled with letters a through h. In the solution we will apply the junction and loop rules, seeking three independent equations to allow us to solve for the three unknown currents.
Solution
We begin by applying Kirchhoff’s first or junction rule at point a. This gives
\[I_1 = I_2 + I_3,\]
since \(I_1\) flows into the junction, while \(I\) and \(I_3\) flow out. Applying the junction rule at e produces exactly the same equation, so that no new information is obtained. This is a single equation with three unknowns—three independent equations are needed, and so the loop rule must be applied.
Now we consider the loop abcdea. Going from a to b, we traverse \(R_2\) in the same (assumed) direction of the current \(I_2\), and so the change in potential is \(-I_2R_2\). Then going from b to c, we go from - to +, so that the change in potential is \(+emf_1\). Traversing the internal resistance \(r_1\) from c to d gives \(-I_2r_1\). Completing the loop by going from d to a again traverses a resistor in the same direction as its current, giving a change in potential of \(-I_1R_1\).
The loop rule states that the changes in potential sum to zero. Thus,
\[-I_2R_2 + emf_1 -I_2r_1 - I_1R_1 = -I_2(R_2 + r_1) + emf_1 - I_1R_1 = 0.\]
Note that the signs are reversed compared with the other loop, because elements are traversed in the opposite direction. With values entered, this becomes \[+6I_1 + 2I_3 -45 = 0.\] These three equations are sufficient to solve for the three unknown currents. First, solve the second equation for \(I_2\).
\[I_2 = 6 - 2I_1.\]
Now solve the third equation for \(I_3\):
\[I_3 = 22.5 - 3I_1.\]
Substituting these two new equations into the first one allows us to find a value for
\[I_1 = I_2 + I_3 = (6 - 2I_1) + (22.5 - 3I_1) = 28.5 - 5I_1.\]
Combining terms gives
\[6I_1 = 28.5, \, and\]\[I_1 = 4.75 \, A.\]
Substituting this value for \(I\) back into the fourth equation gives
\[I_2 = 6 - 2I_1 = 6 - 9.50\]\[I_2 = -3.50 \, A\]
The minus sign means \(I_2\) flows in the direction opposite to that assumed in Figure .
Finally, substituting the value for \(I_1\) into the fifth equation gives
\[I_3 = 22.5 - 3I_1 = 22.5 - 14.25\]\[I_3 = 8.25 \, A.\]
Discussion
Just as a check, we note that indeed \(I_1 = I_2 + I_3\). The results could also have been checked by entering all of the values into the equation for the abcdefgha loop.
Problem-Solving Strategies for Kirchhoff’s Rules
- Make certain there is a clear circuit diagram on which you can label all known and unknown resistances, emfs, and currents. If a current is unknown, you must assign it a direction. This is necessary for determining the signs of potential changes. If you assign the direction incorrectly, the current will be found to have a negative value—no harm done.
- Apply the junction rule to any junction in the circuit. Each time the junction rule is applied, you should get an equation with a current that does not appear in a previous application—if not, then the equation is redundant.
- Apply the loop rule to as many loops as needed to solve for the unknowns in the problem. (There must be as many independent equations as unknowns.) To apply the loop rule, you must choose a direction to go around the loop. Then carefully and consistently determine the signs of the potential changes for each element using the four bulleted points discussed above in conjunction with Figure .
- Solve the simultaneous equations for the unknowns. This may involve many algebraic steps, requiring careful checking and rechecking.
- Check to see whether the answers are reasonable and consistent. The numbers should be of the correct order of magnitude, neither exceedingly large nor vanishingly small. The signs should be reasonable—for example, no resistance should be negative. Check to see that the values obtained satisfy the various equations obtained from applying the rules. The currents should satisfy the junction rule, for example.
The material in this section is correct in theory. We should be able to verify it by making measurements of current and voltage. In fact, some of the devices used to make such measurements are straightforward applications of the principles covered so far and are explored in the next modules. As we shall see, a very basic, even profound, fact results—making a measurement alters the quantity being measured.
Exercise \(\PageIndex{1}\)
Can Kirchhoff’s rules be applied to simple series and parallel circuits or are they restricted for use in more complicated circuits that are not combinations of series and parallel?
- Answer
-
Kirchhoff's rules can be applied to any circuit since they are applications to circuits of two conservation laws. Conservation laws are the most broadly applicable principles in physics. It is usually mathematically simpler to use the rules for series and parallel in simpler circuits so we emphasize Kirchhoff’s rules for use in more complicated situations. But the rules for series and parallel can be derived from Kirchhoff’s rules. Moreover, Kirchhoff’s rules can be expanded to devices other than resistors and emfs, such as capacitors, and are one of the basic analysis devices in circuit analysis.
Summary
- Kirchhoff’s rules can be used to analyze any circuit, simple or complex.
- Kirchhoff’s first rule—the junction rule: The sum of all currents entering a junction must equal the sum of all currents leaving the junction.
- Kirchhoff’s second rule—the loop rule: The algebraic sum of changes in potential around any closed circuit path (loop) must be zero.
- The two rules are based, respectively, on the laws of conservation of charge and energy.
- When calculating potential and current using Kirchhoff’s rules, a set of conventions must be followed for determining the correct signs of various terms.
- The simpler series and parallel rules are special cases of Kirchhoff’s rules.
Glossary
- Kirchhoff’s rules
- a set of two rules, based on conservation of charge and energy, governing current and changes in potential in an electric circuit
- junction rule
- Kirchhoff’s first rule, which applies the conservation of charge to a junction; current is the flow of charge; thus, whatever charge flows into the junction must flow out; the rule can be stated \(I_1 = I+2 + I_3\)
- loop rule
- Kirchhoff’s second rule, which states that in a closed loop, whatever energy is supplied by emf must be transferred into other forms by devices in the loop, since there are no other ways in which energy can be transferred into or out of the circuit. Thus, the emf equals the sum of the \(IR\) (voltage) drops in the loop and can be stated: \(emf = Ir + IR_1 + IR_2\)
- conservation laws
- require that energy and charge be conserved in a system


30.4: Questions you may want to ask yourself as you plan your next observation
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- Last updated
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- Gina Peterson and Emily Elam
- College of the Canyons
When should I observe?
From the moment a child walks into their classroom until the time they leave, opportunities to learn are occurring. Some observations will happen spontaneously, while others will be scheduled. To see a child’s full potential, you will need to observe at various times throughout the day. For example, some children are slow-to-warm and it may take them some time to get acclimated before they can fully engage and interact with others. If a child is slow -to-warm, the morning drop-off may not be the best time to document their social development. You will want to track them throughout the day, at various times (including transition times and snack/meal times), to get a full picture of who they are and what they can do.
Where should I observe?
Many times, observations are centered around structured, teacher-directed activities. This is, in fact, a perfect time to witness what major milestones a child has mastered. However, observing a child while they are exploring in the dramatic play area ( inside ) or while they are in the sandbox area ( outside ) can prove to be just as enlightening. During child-directed play or open exploration, you will no doubt be able to document many of the developmental skills as suggested in the DRDP or Rating Scales, especially how they communicate, cooperate, solve dilemmas and create. Because children can play and learn differently while they are inside as compared to when they are outside, it is necessary to observe in both environments. Likewise, it is important to observe in all activity areas and play spaces.
What observation method should I use?
Use a variety of methods to record and document your children. You will want to “try out” several tools and techniques to find your “go to” method. Because each tool has a specific purpose or focus, using a variety of methods will provide you with sound documentation data to better understand the whole child’s development. Note: In the next chapter, you will examine the various tools and techniques more closely.
Who should I observe?
You will want to observe each child as individuals, and you will want to track group interactions. Becoming aware of who is in your class is necessary if you are going to create a caring classroom community and respectful learning environment. Look for those who are the leaders in your group; find out who needs more one-to-one support and who are your helpers; watch for who plays with who. This insight can help you organize peer scaffolding opportunities which can free up some of your time. As a gentle reminder, sometimes we connect with certain children for one reason or another, and other times a child may challenge us. Either way we need to regularly observe each child with an open mind and an open heart, and we need to look at children with a clear lens that is free of bias. Each child needs your attention; each child has unique gifts; and each child needs your support.
What is the focus of my observation, what am I looking for?
With focused observations, there usually is a specific goal in mind. For example, you might want to know what milestones a child has mastered. For that, you would use a developmental checklist to “check-off” all the skills the child was observed doing.  For that, you can use a frequency count to tally up all the areas and activities the child used during that observation. Keep in mind that you can observe several skills and competencies across multiple domains during one observation. For example, one day you might set out a math activity and the children are expected to create patterns using colorful beads and pipe cleaners, While they work and play, you can listen to the children’s conversations as they describe the patterns they are making; and you can note their fine motor development based on how well they string the beads onto the pipe cleaner; you can also see how they shared space and materials with their peers. Although this was a math activity, many other areas of development can be observed.


10: Experimental Research
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Experimental research—often considered to be the ‘gold standard’ in research designs—is one of the most rigorous of all research designs. In this design, one or more independent variables are manipulated by the researcher (as treatments), subjects are randomly assigned to different treatment levels (random assignment), and the results of the treatments on outcomes (dependent variables) are observed. The unique strength of experimental research is its internal validity (causality) due to its ability to link cause and effect through treatment manipulation, while controlling for the spurious effect of extraneous variable.
Experimental research is best suited for explanatory research—rather than for descriptive or exploratory research—where the goal of the study is to examine cause-effect relationships. It also works well for research that involves a relatively limited and well-defined set of independent variables that can either be manipulated or controlled. Experimental research can be conducted in laboratory or field settings. Laboratory experiments , conducted in laboratory (artificial) settings, tend to be high in internal validity, but this comes at the cost of low external validity (generalisability), because the artificial (laboratory) setting in which the study is conducted may not reflect the real world. Field experiments are conducted in field settings such as in a real organisation, and are high in both internal and external validity. But such experiments are relatively rare, because of the difficulties associated with manipulating treatments and controlling for extraneous effects in a field setting.
Experimental research can be grouped into two broad categories: true experimental designs and quasi-experimental designs. Both designs require treatment manipulation, but while true experiments also require random assignment, quasi-experiments do not. Sometimes, we also refer to non-experimental research, which is not really a research design, but an all-inclusive term that includes all types of research that do not employ treatment manipulation or random assignment, such as survey research, observational research, and correlational studies.


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2',3' dideoxy CTP chemotherapy
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genome
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regulatory networks
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alternative splicing
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genome projects
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restriction endonucleases
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automated DNA sequencing
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genomic library
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reticulocyte
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autoradiography
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insert DNA
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reverse transcriptase
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BACs and YACs
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library screening
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RNA probes
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bacterial artificial chromosome vectors
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linkers
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RNAse
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blunt ends
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Northern blot
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shotgun sequencing
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cDNA
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oligo d(T) column
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single nucleotide polymorphisms
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cDNA hairpin loop
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PCR
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SNPs
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cDNA library
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PCR primers
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Southern blot
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cDNA probes
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PCR steps
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sticky ends
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chemiluminescence
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phage lambda vectors
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systematics
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cosmid vectors
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plasmids
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Taq polymerase
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di-deoxy chain termination
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poly(A) tail
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thermophilic bacteria
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di-deoxy sequencing method
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polymerase chain reaction
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thermophilic DNA polymerases
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DNA ligase
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primer
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Thermus aquaticus
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DNA sequencing
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primer walking
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transcriptome
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elution
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probe hybridization
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transformation
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ethidium bromide
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proteome
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vectors
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fluorescence
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recombinant vector
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Western blot
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forensics
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recombination
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yeast artificial chromosome vectors
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Genetic (DNA) fingerprint
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4.4: Characteristics of Successful Entrepreneurs
- What characteristics do successful entrepreneurs share?
Do you have what it takes to become an entrepreneur? Having a great concept is not enough. An entrepreneur must be able to develop and manage the company that implements his or her idea. Being an entrepreneur requires special drive, perseverance, passion, and a spirit of adventure, in addition to managerial and technical ability. Entrepreneurs are the company; they tend to work longer hours, take fewer vacations, and cannot leave problems at the office at the end of the day. They also share other common characteristics as described in the next section.
The Entrepreneurial Personality
Studies of the entrepreneurial personality find that entrepreneurs share certain key traits. Most entrepreneurs are
- Ambitious : They are competitive and have a high need for achievement.
- Independent : They are individualists and self-starters who prefer to lead rather than follow.
- Self-confident : They understand the challenges of starting and operating a business and are decisive and confident in their ability to solve problems.
- Risk-takers : Although they are not averse to risk, most successful entrepreneurs favor business opportunities that carry a moderate degree of risk where they can better control the outcome over highly risky ventures where luck plays a large role.
- Visionary : Their ability to spot trends and act on them sets entrepreneurs apart from small-business owners and managers.
- Creative : To compete with larger firms, entrepreneurs must have creative product designs, bold marketing strategies, and innovative solutions to managerial problems.
- Energetic : Starting and operating a business takes long hours. Even so, some entrepreneurs start their companies while still employed full-time elsewhere.
- Passionate : Entrepreneurs love their work, as Miho Inagi demonstrated by opening a bagel shop in Tokyo despite the odds against its being a success.
- Committed : Because enterpreneurs are so committed to their companies, they are willing to make personal sacrifices to achieve their goals.
Ethical Choices Transform Family Business into International Brand
Ever since Apollonia Poilâne was a young girl growing up in Paris, she always knew what she wanted to do when she grew up: take over the family business. But she didn’t anticipate how quickly this would happen. When her father—Lionel Poilâne—and her mother died in a helicopter crash in 2002, France lost its most celebrated baker, and Apollonia stepped into the role. She was just 18 years old at the time with plans to matriculate to Harvard in the fall, but the moment her parents had prepared her for had come. As her Harvard admissions essay said, “The work of several generations is at stake.”
With organization and determination, Apollonia managed one of the best French bakeries in the world—based in Paris—from her apartment in Cambridge, Massachusetts. She would usually wake up an extra two hours before classes to ensure she would get all the phone calls done for work. “After classes, I check on any business regarding the company and then do my homework,” she says. “Before I go to bed, I call my production manager in Paris to check the quality of the bread.” Because the name Poilâne has earned a place with a very small group of prestige bakers, the 18-year-old was determined to continue the tradition of customer satisfaction and quality her grandfather established in 1932. When her grandfather suffered a stroke in 1973, his 28-year-old son, Lionel, poured his heart into the business and made the family bread into the global brand it is today. Lionel opened two more bakeries in Paris and another in London. He developed and nurtured a worldwide network of retailers and celebrities where bread is shipped daily via FedEx to upscale restaurants and wealthy clients around the world.
Experimenting with sourdough is what distinguished Poilâne’s products from bread produced by Paris’s other bakers, and it has remained the company’s signature product. It is baked with a “P” carved into the crust, a throwback to the days when the use of communal ovens forced bakers to identify their loaves, and it also ensures that the loaf doesn’t burst while it’s baking. Today, Poilâne also sells croissants, pastries, and a few specialty breads, but the company’s signature item is still the four-poundmiche, a wheel of sourdough, a country bread, pain Poilâne .
“Apollonia is definitely passionate about her job,” says Juliette Sarrazin, manager of the successful Poilâne Bakery in London. “She really believes in the work of her father and the company, and she is looking at the future, which is very good.”
Apollonia’s work ethic and passion fueled her drive even as a student. Each day presented a juggling act of new problems to solve in Paris while other Harvard students slept. As Apollonia told a student reporter from The Harvard Crimson , “The one or two hours you spend procrastinating, I spend working. It’s nothing demanding at all. It has always been my dream to run a company.”
Her dedication paid off, and Apollonia retained control of important decisions, strategy, and business goals, describing herself as the “commander of the ship,” determining the company’s overall direction. Today, Poilâne is an $18 million business that employs 160 people. Poilâne runs three restaurants called Cuisine de Bar in Paris and London, serving casual meals such as soups, salads, and open-faced tartines . The company ships more than 200,000 loaves a year to clients in 20 countries, including the United States, Japan, and Saudi Arabia. “More people understand what makes the quality of the bread, what my father spent years studying, so I am thrilled about that,” says Apollonia.
Critical Thinking Questions
- What type of entrepreneur is Apollonia Poilâne?
- What personal ethics drove Apollonia’s decision to take over the family business?
Sources:
Antoine, C. (2003). No time to loaf around. Harvard Crimson. http://www.thecrimson.com . October 16, 2003.
Bortin, M. (2018). Apollonia Poilâne builds on her family’s legacy. The New York Times. https://www.nytimes.com .
Collins, L. (2012). Bread winner: A daughter upholds the traditions of France’s premier baking dynasty. The New Yorker. December 3, 2012. https://www.newyorker.com ,
Katz, G. (2005). Her daily bread. American Way Magazine.
Poilâne. (2018). About us. https://www.poilane.com .
Most entrepreneurs combine many of the above characteristics. Sarah Levy, 23, loved her job as a restaurant pastry chef but not the low pay, high stress, and long hours of a commercial kitchen. So she found a new one—in her parents’ home—and launched Sarah’s Pastries and Candies. Part-time staffers help her fill pastry and candy orders to the soothing sounds of music videos playing in the background. Cornell University graduate Conor McDonough started his own web design firm, OffThePathMedia.com, after becoming disillusioned with the rigid structure of his job. “There wasn’t enough room for my own expression,” he says. “Freelancing keeps me on my toes,” says busy graphic artist Ana Sanchez. “It forces me to do my best work because I know my next job depends on my performance” (Irvine, 2004).
Managerial Ability and Technical Knowledge
A person with all the characteristics of an entrepreneur might still lack the necessary business skills to run a successful company. Entrepreneurs need the technical knowledge to carry out their ideas and the managerial ability to organize a company, develop operating strategies, obtain financing, and supervise day-to-day activities. Jim Crane, who built Eagle Global Logistics from a start-up into a $250 million company, addressed a group at a meeting, saying, “I have never run a $250 million company before, so you guys are going to have to start running this business” (McFarland, 2005).
Good interpersonal and communication skills are important in dealing with employees, customers, and other business associates such as bankers, accountants, and attorneys. As discussed in the chapter, entrepreneurs believe they can learn these much-needed skills. When Jim Steiner started his toner cartridge remanufacturing business, Quality Imaging Products, his initial investment was $400. He spent $200 on a consultant to teach him the business and $200 on materials to rebuild his first printer cartridges. He made sales calls from 8.00 a.m. to noon and made deliveries to customers from noon until 5:00 p.m. After a quick dinner, he moved to the garage, filling copier cartridges until midnight, when he collapsed into bed, sometimes covered with carbon soot. This was not something he did for a couple of months until he got the business off the ground—this was his life for 18 months (McFarland, 2005). But entrepreneurs usually soon learn that they can’t do it all themselves. Often, they choose to focus on what they do best and hire others to do the rest.
- Describe the personality traits and skills characteristic of successful entrepreneurs.
- What does it mean when we say that an entrepreneur should work on the business, not in it?